Improvement in safety-tackle



UNITED STATES ATEN'P VOEEICE.

PIERRE JosEPH JAMET, oE PARIS, FRANCE.

IMPROVEMENT IN SAFETY-TACKLE.

Specication forming part of Letters Patent No. 4&0311, dated May 30,E65.

To @ZZ whom t may concern:

Be it known that I, P. J. JAMT, of Paris, in the Empire of France, haveinvented certain new and useful Improvements in Safety- Tackle, and Ihereby declare that the following is a full, clear, and exactdescription of the same, reference being had to the accompanyingdrawings.

The objectief my invention is the construction of a tackle possessingthe advantage of holding in suspension a load at any given ele vationwithout securing or tying the cord upon which the operator pulls, andthis is accomplished by means of a vibratory frame or block hung in asuitable link ofthe stationary hook and by means of a lever or brake.

In the accompanying drawings, Figure 'l is a side view, Fig. 2 a frontelevation, and Fig. 3 a detail view, of my improved tackle.

The movable block may be constructed in the ordinary or in any suitablemanner. The

stationary block is composed ot' a suspensionhook, G, pivoted on `across-head, t, which unites the two pendent side links, p p. The hookproper is common to all tackles. Between the two links p and p', andupon va eentral pin or axle, Z, is hung the frame J J of;

the sheaves, and is composed of two plates united together by meansofstay-bolts a a a". These two plates thus arranged are capable ofoscillation upon their point of suspension at Zto the extent determinedby a stop, r, and as shown in Fig. 2. The sheaves or pulleys g g g",which support the load, are mounted upon an axle, Z, on the left side ofthe links p, and the rope or cord passes over another pulley or sheave,b, on the right side ot' the link, and mounted upon an aXle, Z, so thaton pulling upon the cord or rope X the frame J will be brought intoposition indicated in black lines, and when released assume the positionindicated in blue lines, and thus produce oscillation at each pull onthe rope. oscillatory movement which enables me to stop at pleasure, asthough with a brake, the backward movement of the pulleys when actuatedby the weight ofthe load to be hoisted and when the strain on the ropeis released. In Fig. 3 the position of the pulley b in relationto thecross-head is Vthat indicated in blue lines in Fig. 2. The cord or ropepassing It is thisV around the sheave or pulley b is pinched orcompressed between the pulley and a recess or gorge formed in thecross-head t with a force proportionate to the weight to be raised. Itwill be understood that on again pulling 0n the cord Xthe frame will becaused to assume the position in black lines and the load to ascend.Upon the pin or axle Z is arranged a cam-lever, q, the oi'iice ofwhicnis to allow the weight or load or movable pulley to descend, should thatbe necessary. To this effect the lever at its upper end is provided witha cam, the shoulder e of which, when engaged with the edge ofthecross-head t, prevents brake action or the cord being bound as beforedescribed. This cam is operated by means of the curved shank of thelever, the lower end of which is formed into an eye, thr ugh which thecord X passes. When, therefore, it is desired to allow the weight todescend, the shank is drawn by means of the oord, so that the shoulderor notch e falls in with the edge of the cross-head. Thiskind of tackleis applicable to the lifting of weights of all sorts on board of ships,in wells, upon lseat-folding or derricks. zc.

Having now described my said invention, I claiml. The construction,substantially as herein operated by the rope or otherwise, under thearrangement described, so as to prevent brake action, in the manner andfor the purpose set forth.

In testimony whereof Ihave signed my name to this specification beforetwo subscribing witnesses.

JAME'T.

Witnesses: G. EORTIER,

EDWARD TUGK.

